汽轮机排汽焓误差对等效热降法计算结果影响的研究

等效热降法计算中需要预先已知汽轮机的排汽焓,而对于凝汽式汽轮机,其排汽状态点常处于湿蒸汽区,排汽焓不能准确测定,从而导致等效热降法计算结果产生误差。首先建立了回热系统某因素发生变化时,由于排汽焓测量存在误差,导致利用等效热降法计算结果产生相应的误差的计算模型,然后针对某200MW机组高压阀杆漏汽增加和加热器端差增大对汽轮机热经济性影响的问题,计算排汽焓误差对其计算结果的影响。

Research on Steam Turbine Exhaust Enthalpy Error Enfluencing on Computed Result Based on Equivalent Enthalpy Drop

Steam turbine exhaust enthalpy is known in calculation using the equivalent enthalpy drop method.Exhaust steam condition point is usually in the wet vapor region so that exhaust enthalpy can't be confirmed exactly for condenser steam turbine.Exhaust enthalpy error make calculation result produce error using the equivalent enthalpy drop method.Calculation error model is presented when one parameter of regenerative system changes.Then,to counter the problem that control valve stem leakoff increasing or heater terminal difference increasing affects on heat economy of steam turbine about a 200MW generation unit,calculation is done about exhaust enthalpy error affecting on calculation result.